PVAC adhesive test

PVAc-based commercial wood adhesives are evaluated using standard tests for non-structural applications, as reported in EN 205 [8], and they are classified in agreement with the standard EN-204 [9]. This standard allows to classify wood adhesives in 4 categories from D1 to D4. D1 adhesives show a good resistance only in dry conditions D2 adhesives should withstand a rather low water presence, such as in occasional exposure in kitchens and bathrooms D3 adhesives are suitable to come in contact with cold water, such as for outside windows and doors, kitchen and bathrooms furniture D4 adhesives are suitable to be used in extreme conditions (resistance to hot water). Vinyl acetate homopolymer can be used to formulate D1 or D2 adhesives. Vinyl acetate based adhesives cross-Unked with hardeners and urea-formaldehyde (UF) adhesives belong to class D3. Only the phenol-formaldehyde (PE), resorcinol-formaldehyde (RF) and melamine-formaldehyde (MF) adhesives, some special 2-component polyurethanes (PUs), and cross-linking vinyl adhesives belong to class D4. 

The PVAc homopolymer (1) and the VAc/Unseed oil (10%) copolymer (2) obtained in organic solvent were tested using the EN205-D3 test. In agreement with this test the adhesive strength can be measured in dry conditions (D3-1) or in wet conditions (D3-3). The presence of ethyl acetate as solvent (solid content 50%)... 

Most of the glued components produced in Europe for non-structural purposes such as joinery use urea-formaldehyde (UF), poly (vinyl acetate) (PVAc) or polyurethane (PUR) adhesives. These adhesives must meet the performance requirements specified in EN 204 (2002) [15] for thermoplastic adhesives or EN 12765 (2002) [16] for thermosetting adhesives when tested in accordance with the following test methods ... 

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